Wireless sensor networks are known to be used in process control systems. Examples on such networks are ZigBee and WirelessHart, ISA100, WIA-PA and Bluetooth. There also exist some WLAN based sensor networks.
In such systems packets may remain in the system waiting for transmission for a long time. This may be problematic for a number of reasons. An old packet may be useless. In for instance process control an old measurement value is at best of no use and harmless and at worst harmful and may lead to problems in the control. Furthermore if there are old packets in the system, the system resources are not used efficiently. Useful data may wait in a buffer for transmission as useless data is being transmitted.
There is therefore a need for prioritizing transmissions.
Prioritization in a mobile phone system is for instance described in U.S. Pat. No. 7,668,150, while US 2011/0176521 describes prioritization of packets in a wireless sensor network.
However, there is still a need for improvement within the field.
There is therefore a need for an improvement in relation to industrial wireless networks.